shorewall-providers(5)
NAME
providers - Shorewall Providers file
SYNOPSIS
/etc/shorewall/providers
DESCRIPTION
This file is used to define additional routing tables. You will want to
define an additional table if:
* You have connections to more than one ISP or multiple connections
to the same ISP
* You run Squid as a transparent proxy on a host other than the
firewall.
* You have other requirements for policy routing.
Each entry in the file defines a single routing table.
If you wish to omit a column entry but want to include an entry in the
next column, use "-" for the omitted entry.
The columns in the file are as follows.
NAME - name
The provider name. Must be a valid shell variable name. The names
'local', 'main', 'default' and 'unspec' are reserved and may not be
used as provider names.
NUMBER - number
The provider number -- a number between 1 and 15. Each provider
must be assigned a unique value.
MARK (Optional) - value
A FWMARK value used in your shorewall-mangle(5)[1] file to direct
packets to this provider.
If HIGH_ROUTE_MARKS=Yes in shorewall.conf(5)[2], then the value
must be a multiple of 256 between 256 and 65280 or their
hexadecimal equivalents (0x0100 and 0xff00 with the low-order byte
of the value being zero). Otherwise, the value must be between 1
and 255. Each provider must be assigned a unique mark value. This
column may be omitted if you don't use packet marking to direct
connections to a particular provider.
DUPLICATE - routing-table-name
The name of an existing table to duplicate to create this routing
table. May be main or the name of a previously listed provider. You
may select only certain entries from the table to copy by using the
COPY column below. This column should contain a dash ("-') when
USE_DEFAULT_RT=Yes in shorewall.conf(5)[2].
INTERFACE - interface[:address]
The name of the network interface to the provider. Must be listed
in shorewall-interfaces(5)[3]. In general, that interface should
not have the proxyarp option specified unless loose is given in the
OPTIONS column of this entry.
Where more than one provider is serviced through a single
interface, the interface must be followed by a colon and the IP
address of the interface that is supplied by the associated
provider.
GATEWAY - {-|address[,mac]|detect|none}
The IP address of the provider's gateway router. Beginning with
Shorewall 4.6.2, you may also specify the MAC address of the
gateway when there are multiple providers serviced through the same
interface. When the MAC is not specified, Shorewall will detect the
MAC during firewall start or restart.
You can enter detect here and Shorewall will attempt to detect the
gateway automatically.
Beginning with Shorewall 5.0.6, you may also enter none. This
causes creation of a routing table with no default route in it.
For PPP devices, you may omit this column.
OPTIONS (Optional) - [-|option[,option]...]
A comma-separated list selected from the following. The order of
the options is not significant but the list may contain no embedded
white-space.
autosrc
Added in Shorewall 4.5.17. Causes a host route to the
provider's gateway router to be added to the provider's routing
table. This is the default behavior unless overridden by a
following noautosrc option.
track
If specified, inbound connections on this interface are to be
tracked so that responses may be routed back out this same
interface.
You want to specify track if internet hosts will be connecting
to local servers through this provider.
Beginning with Shorewall 4.4.3, track defaults to the setting
of the TRACK_PROVIDERS option in shorewall.conf[2] (5). If you
set TRACK_PROVIDERS=Yes and want to override that setting for
an individual provider, then specify notrack (see below).
balance[=weight]
The providers that have balance specified will get outbound
traffic load-balanced among them. By default, all interfaces
with balance specified will have the same weight (1). You can
change the weight of an interface by specifying balance=weight
where weight is the weight of the route out of this interface.
loose
Shorewall normally adds a routing rule for each IP address on
an interface which forces traffic whose source is that IP
address to be sent using the routing table for that interface.
Setting loose prevents creation of such rules on this
interface.
load=probability
Added in Shorewall 4.6.0. This option provides an alternative
method of load balancing based on probabilities. Providers to
be balanced are given a probability (a number 0 > n >= 1) with
up to 8 digits to the right of the decimal point. Beginning
with Shorewall 4.6.10, a warning is issued if the sum of the
probabilities is not 1.00000000.
noautosrc
Added in Shorewall 4.5.17. Prevents the addition of a host
route to the provider's gateway router from being added to the
provider's routing table. This option must be used with caution
as it can cause start and restart failures.
notrack
Added in Shorewall 4.4.3. When specified, turns off track.
optional (deprecated for use with providers that do not share an
interface)
If the interface named in the INTERFACE column is not up and
configured with an IPv4 address then ignore this provider. If
not specified, the value of the optional option for the
INTERFACE in shorewall-interfaces(5)[3] is assumed. Use of that
option is preferred to this one, unless an address is provider
in the INTERFACE column.
primary
Added in Shorewall 4.6.6, primary is equivalent to balance=1
and is preferred when the remaining providers specify fallback
or tproxy.
src=source-address
Specifies the source address to use when routing to this
provider and none is known (the local client has bound to the 0
address). May not be specified when an address is given in the
INTERFACE column. If this option is not used, Shorewall
substitutes the primary IP address on the interface named in
the INTERFACE column.
mtu=number
Specifies the MTU when forwarding through this provider. If not
given, the MTU of the interface named in the INTERFACE column
is assumed.
fallback[=weight]
Indicates that a default route through the provider should be
added to the default routing table (table 253). If a weight is
given, a balanced route is added with the weight of this
provider equal to the specified weight. If the option is given
without a weight, an separate default route is added through
the provider's gateway; the route has a metric equal to the
provider's NUMBER.
Prior to Shorewall 4.4.24, the option is ignored with a warning
message if USE_DEFAULT_RT=Yes in shorewall.conf.
tproxy
Added in Shorewall 4.5.4. Used for supporting the TPROXY action
in shorewall-mangle(5). See
http://www.shorewall.net/Shorewall_Squid_Usage.html[4]. When
specified, the MARK, DUPLICATE and GATEWAY columns should be
empty, INTERFACE should be set to 'lo' and tproxy should be the
only OPTION. Only one tproxy provider is allowed.
hostroute
Added in Shorewall 4.5.21. This is the default behavior that
results in a host route to the defined GATEWAY being inserted
into the main routing table and into the provider's routing
table. hostroute is required for older distributions but
nohostroute (below) is appropriate for recent distributions.
hostroute may interfere with Zebra's ability to add routes on
some distributions such as Debian 7.
nohostroute
Added in Shorewall 4.5.21. nohostroute inhibits addition of a
host route to the defined GATEWAY being inserted into the main
routing table and into the provider's routing table.
nohostroute is not appropriate for older distributions but is
appropriate for recent distributions. nohostroute allows
Zebra's to correctly add routes on some distributions such as
Debian 7.
persistent
Added in Shorewall 5.0.2 and alters the behavior of the disable
command:
* The provider's routing table still contains the apprioriate
default route.
* Unless the noautosrc option is specified, routing rules are
generated to route traffic from the interfaces address(es)
out of the provider's routing table.
* Persistent routing rules in shorewall-rtrules(5)[5] are
present.
Note
The generated script will attempt to reenable a disabled
persistent provider during execution of the start, restart
and reload commands. When persistent is not specified, only
the enable and reenable commands can reenable the provider.
COPY - [{none|interface[,interface]...}]
A comma-separated list of other interfaces on your firewall.
Wildcards specified using an asterisk ("*") are permitted (e.g.,
tun* ). Usually used only when DUPLICATE is main. Only copy routes
through INTERFACE and through interfaces listed here. If you only
wish to copy routes through INTERFACE, enter none in this column.
Beginning with Shorewall 4.5.17, blackhole, unreachable and
prohibit routes are no longer copied by default but may be copied
by including blackhole,unreachable and prohibit respectively in the
COPY list.
EXAMPLES
Example 1:
You run squid in your DMZ on IP address 192.168.2.99. Your DMZ
interface is eth2
#NAME NUMBER MARK DUPLICATE INTERFACE GATEWAY OPTIONS
Squid 1 1 - eth2 192.168.2.99 -
Example 2:
eth0 connects to ISP 1. The IP address of eth0 is 206.124.146.176
and the ISP's gateway router has IP address 206.124.146.254.
eth1 connects to ISP 2. The IP address of eth1 is 130.252.99.27 and
the ISP's gateway router has IP address 130.252.99.254.
eth2 connects to a local network.
#NAME NUMBER MARK DUPLICATE INTERFACE GATEWAY OPTIONS COPY
ISP1 1 1 main eth0 206.124.146.254 track,balance eth2
ISP2 2 2 main eth1 130.252.99.254 track,balance eth2
FILES
/etc/shorewall/providers
SEE ALSO
http://www.shorewall.net/MultiISP.html[6] http://www.shorewall.net/configuration_file_basics.htm#Pairs[7] shorewall(8), shorewall-accounting(5), shorewall-actions(5), shorewall-blacklist(5), shorewall-hosts(5), shorewall_interfaces(5), shorewall-ipsets(5), shorewall-maclist(5), shorewall-masq(5), shorewall-nat(5), shorewall-netmap(5), shorewall-params(5), shorewall-policy(5), shorewall-proxyarp(5), shorewall-rtrules(5), shorewall-routestopped(5), shorewall-rules(5), shorewall.conf(5), shorewall-secmarks(5), shorewall-tcclasses(5), shorewall-tcdevices(5), shorewall-mangle(5), shorewall-tos(5), shorewall-tunnels(5), shorewall-zones(5)
NOTES
1. shorewall-mangle(5)
http://www.shorewall.net/manpages/shorewall-mangle.html
2. shorewall.conf(5)
http://www.shorewall.net/manpages/shorewall.conf.html
3. shorewall-interfaces(5)
http://www.shorewall.net/manpages/shorewall-interfaces.html
4. http://www.shorewall.net/Shorewall_Squid_Usage.html
http://www.shorewall.net/Shorewall_Squid_Usage.html
5. shorewall-rtrules(5)
http://www.shorewall.netshorewall-rtrules.html
6. http://www.shorewall.net/MultiISP.html
http://www.shorewall.net/MultiISP.html
7. http://www.shorewall.net/configuration_file_basics.htm#Pairs
http://www.shorewall.net/configuration_file_basics.htm#Pairs
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